Device for blowing thermoplastic containers

ABSTRACT

A device for blowing, with the aid of a pressurized fluid, containers from thermoplastic blanks closed in a blow mold including a nozzle whose end is functionally and sealingly connected to the neck of the blank and includes several solenoid valves for selectively connecting the nozzle to the source of a moderately pressurized pre-blowing fluid, to the source of a highly-pressurized blowing fluid and to an exhaust for discharging the pre-blowing/blowing fluid, respectively. The inventive device also includes a body which is mechanically associated with the nozzle, incorporates at least one reception area for receiving a solenoid valve and is selectively connectable to the nozzle.

FIELD OF THE INVENTION

The present invention generally relates to the field of manufacturingcontainers made from thermoplastic material, such as PET or PEN, by ablowing or stretch-blowing method from a blank (preform or intermediatecontainer) and it relates more specifically to improvements made todevices for blowing, by means of a pressurized fluid, containers fromthermoplastic blanks, of which the body is enclosed in a blowing mold,said devices comprising a nozzle consisting of an end formed to befunctionally and sealingly connected to the neck of a blank andcomprising a plurality of solenoid valves for selectively connectingsaid nozzle to, for example, respectively a source of fluid at moderatepressure for pre-blowing, a source of fluid at high pressure for blowingand an exhaust for discharging the pre-blowing/blowing fluid.

BACKGROUND OF THE INVENTION

As known, the nozzle is designed to be axially mobile, in its entiretyor partially, above the blowing mold between an upper position or raisedposition in which the nozzle is not functional (opening and closing ofthe mold allowing the loading of a blank and the release of the moldedcontainer) and a lower position or blowing position in which the end ofthe nozzle cooperates sealingly either with the neck of the blank, orwith the face of the mold above which the neck of the blank projects andin which the nozzle is functional.

Blowing devices are known in which the end of the nozzle, in thefunctional position, cooperates positively with the neck of the blankand either sealingly abuts against the lip (edge) of the neck of theblank, or is sealingly fitted into or onto the neck of the blank.

Blowing devices are also known in which the end of the nozzle isconfigured in the shape of a bell which is larger than the neck of theblank and caps said neck by being sealingly supported at the frontagainst the face of the mold on which the neck of the blank projects(see, for example, the document FR 2 764 544).

A blowing sequence normally consists of a step of pre-blowing the blankby means of a fluid (generally air) at moderate pressure (for example7×10⁵ Pa), then the blowing step itself, at high pressure (for example40×10⁵ Pa) generally accompanied by mechanical axial stretching by meansof a stretch rod and finally an exhaust step with the discharge of thepre-blowing/blowing air. For these various steps, three respectivesolenoid valves are controlled sequentially which, on the one hand, arerespectively connected to a source of fluid at moderate pressure, asource of fluid at high pressure and an exhaust and which, on the otherhand, are connected to the nozzle.

A blowing device of the type under consideration consumes a very largeamount of pressurized fluid, whether at moderate or high pressure. Theconstant production of pressurized fluid (air) in large quantities leadsto a very high consumption of electrical energy for the functioning ofthe compressor(s). As a result, there is a constant and urgent demand onthe part of the users of these blowing devices for as large a reductionas possible of the quantity of pressurized fluid used, so as to reducethe consumption of electrical energy.

It must be understood that the only useful volume for the blowingoperation is the volume of the container forced into its final shapeagainst the walls of the molding cavity of the mold, in other words,substantially the volume of the molding cavity. In contrast, all thevolumes located between the outlet of the pre-blowing or blowingsolenoid valve and the neck of the container are, strictly speaking,volumes which are superfluous for the deformation of the blank and aretherefore dead volumes. At each step for pre-blowing and blowing ablank, these dead volumes are filled with pressurized fluid in the samemanner as the useful volume, which involves a production of pressurizedfluid which is substantially greater than the actual requirement. Thedead volumes are of a size which is not inconsiderable relative to theuseful volumes and any reduction of these dead volumes proves beneficialin terms of a possible reduction in the power of the fluid compressorand therefore of its cost, and in terms of reducing the electricalenergy required for the functioning of the compressor.

In a first design of the blowing device, the solenoid valves weregrouped together on a fixed base mounted on the frame remote from thenozzle. A flexible tube connected the common outlet of the solenoidvalves to the connecting aperture of the nozzle (for example the tube 23in FIG. 1 of the aforementioned document FR 2 764 544). In this design,the dead volume was very large, in particular due to the presence of theflexible tube for remote connection.

In a subsequent design, the dead volume has been markedly reduced byeliminating the flexible connecting tube and by mounting the solenoidvalve block directly on the body of the nozzle, at the location forconnecting the tube 23 in FIG. 1 of the document FR 2 764 544.Nevertheless, in this design which currently continues to exist, thejuxtaposition of the two respective bodies of the solenoid valve blockand of the nozzle further necessitates fluid passages of a sizeablelength, which results in a dead volume which is still too large in termsof consumption. As a result, users uphold their demand for a still lowerconsumption of pressurized fluid, so as to reduce further theconsumption of electrical energy.

Furthermore, the presence of solenoid valve blocks located remotely fromthe nozzle or juxtaposed therewith leads to a heavy and awkwardassembly.

BRIEF DESCRIPTION OF THE INVENTION

The object of the invention is, therefore, to attempt to satisfy, as faras possible, these continued requirements of users and to propose animproved arrangement of the blowing device which leads to a verysubstantial reduction in the dead volumes in the circuit for supplyingpressurized fluid to the blank arranged in the molding cavity of themold and which may also lead to lighter and more compact structuralassemblies.

To these ends, a blowing device as set forth in the preamble ischaracterized, being designed in accordance with the invention, in thata body associated mechanically with the nozzle incorporates at least onehousing which is adapted to accommodate one respective solenoid valve,which is selectively in communication with the nozzle.

Due to this integrated structure, the outlet of the solenoid valve ismoved considerably closer to the end of the nozzle, and as a result thedead volume is considerably reduced in accordance with the principalobject sought.

It will be noted that such an integrated arrangement also offersadditional advantages: the elimination of the base for mounting thesolenoid valves and possibly the flexible connection, results in asaving in cost (more economical arrangement), a saving in space(possibility of a more compact arrangement and/or space available formounting other components) and a saving in weight (reduction in theinertia on a rotating structure of the carousel type).

In a preferred embodiment relating, in particular, to nozzles inpositive cooperation with the neck of the blanks, it is the bodysupporting the nozzle which is provided with the above housing.Nevertheless, in a further possible embodiment which relates to devicesin which the nozzle is provided with a bell-shaped end part, it is thebody of said bell which is designed with said housing. In theembodiments, it may be provided that the housing extends parallel to theaxis of the nozzle from the upper face of the body, or that the housingextends radially from the nozzle, or even that the housing extendstransversely to the nozzle, by being offset laterally relative to a boreaccommodating said nozzle.

In a first possible embodiment of the arrangements according to theinvention, each housing may be machined so as to form the respectivechamber of the mobile core of the solenoid valve; in other words, therespective part of the body is machined, so as not only to form thehousing there, but also so that said housing is adapted to receivedirectly the mobile core of the solenoid valve. This solution offers theadvantage of a maximum reduction of the number of component parts andmay achieve a substantial saving in the dead volumes; nevertheless, thismaximally integrated structure is shown to be impractical formaintenance, as dismantling is lengthy and/or in the case of a seriousproblem on the chamber of the solenoid valve, the entire correspondingpart of the body has to be replaced.

As a result, a preferred implementation of the arrangements of theinvention consists in that each housing is formed to receive arespective solenoid valve cartridge, i.e. a solenoid valve structurecomprising a casing defining a chamber accommodating the mobile core.Maintenance is therefore carried out by simply replacing the cartridge,such an operation being easy and rapid to implement.

Whatever the solution retained, however, it is preferable, still withthe purpose of facilitating maintenance, that the control device of thesolenoid valve is mounted externally on the housing.

In an advantageous version of the device of the invention, an exhaustsolenoid valve is provided and a device acting as a silencer isassociated with this exhaust solenoid valve; the control device of thisexhaust solenoid valve may thus be mounted at the end of said silencerdevice, or possibly at the inside of said device shaped as a tubularchamber.

Finally, from the need to make savings on the pressurized fluidproduction station, it may be provided to implement two solenoid valvesin the exhaust circuit and to provide the nozzle body with two housingsfor these two respective solenoid valves, one of these solenoid valvesbeing associated with a circuit for recycling or reusing air (forexample by being directed towards a source at reduced pressure) and theother solenoid valve serving to complete the step of discharging to theatmosphere. In such a case, it is this latter solenoid valve which wouldbe associated with the aforementioned silencer device.

Still with the object of maximum reduction of the dead volumes, it mayalso be provided that at least the pre-blowing and blowing solenoidvalves and the respective housings thereof are designed such that in theclosed position the respective front faces of the respective valvemembers of said solenoid valves are flush with the inner wall of thenozzle.

For clarification, in a typical example where three solenoid valves areinstalled, the dead volume may, by implementing the arrangements of theinvention, be reduced to a size of 18.5 cm³, in contrast withapproximately 187 cm³ in a current arrangement, namely a considerablesaving in the order of 168 cm³.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by reading the detaileddescription which follows of certain preferred embodiments given by wayof purely illustrative and non-limiting example. In this description,reference is made to the accompanying drawings in which:

FIG. 1 is a very schematic perspective and lateral view, showing theprincipal arrangements of a blowing device designed according to theinvention;

FIGS. 2A and 2B are views in transverse section, respectively offset by90° relative to one another, of a concrete embodiment of a blowingdevice according to the invention, with the implementation of a variantof the arrangements of FIG. 1;

FIG. 2C is a view similar to that of FIG. 2A, with the nozzle loweredonto the blank to be blown and ready for the blowing process;

FIG. 3 is a view from above, in section, of a concrete embodiment of ablowing device according to the invention, showing a variant of thenozzle of FIGS. 2A-2C;

FIG. 4 is a very schematic and simplified perspective and lateral view,showing a further variant of implementing the arrangements of theinvention; and

FIG. 5 is a partial view showing a variant of the arrangements shown inFIG. 2A.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1, to which reference will be made firstly, shows in a veryschematic manner a simplified structure of a blowing device implementingthe principal arrangements of the invention applied to a device providedwith three solenoid valves (respectively pre-blowing, blowing, exhaust).The blowing device, denoted in its entirety by the reference numeral 1,comprises a body 2 having an axial bore 3 in which may be displaced,under the action of generally pneumatic control means (not shown), amobile element or mobile nozzle 4 in the form of a tubular rod of whichone part (not shown) may be designed in the shape of a piston. Forclarification, the mutual arrangement of the body 2 and of the mobilenozzle 4 may, for example, be of the type shown in FIG. 1 of thedocument FR 2 764 544. At its lower end 5, the mobile nozzle 4 is formedin any desired manner to be able to be functionally and sealinglyconnected to the neck 6 or mouth of a blank 7 of a container (shown herein the form of a preform); in the example shown, the lower end 5 isdesigned, when the mobile nozzle 4 is lowered, to cap the neck 6 of theblank 7 in a sealed manner and to be brought to bear against the flange8 located at the base of said neck; the lower end 5 could also bedesigned to be brought to bear sealingly against the lip or edge 8 a ofthe neck 6, or even be shaped as a bell surrounding the neck 6 remotelyand bearing sealingly against the face of the mold, beyond which theneck 6 and the flange 8 project.

In a conventional manner, the mobile nozzle 4 in the form of a tubularrod surrounds an elongating rod 9 which is coaxial thereto and whichitself may be axially displaced, during blowing, for mechanicallydriving the base of the blank 7 according to a known technique. Theelongating rod 9 is maintained in a coaxial position by guide members,not shown in this figure. The diameter of the elongating rod 9 is lessthan that of the inner face of the mobile nozzle 4 so as to define anannular axial passage 10 designed for the supply of pre-blowing fluidand blowing fluid and for the discharge of said fluid at the end of themolding process.

For controlling the supply and discharge of the pre-blowing/blowingfluid, at least three respective solenoid valves are provided forconnecting the annular passage 10 to one respective source of fluid atmoderate pressure (typically 7×10⁵ Pa) for the pre-blowing, a source offluid at high pressure (typically 40×10⁵ Pa) for the blowing and anexhaust for discharging the pre-blowing/blowing fluid.

In the arrangements currently known, the solenoid valves were arrangedon the outside of the body 2, either remotely thereto (document FR 2 764544) or flat against an external face thereof.

According to the invention, these solenoid valves are incorporated inthe body 2. As shown schematically in FIG. 1, the upper part 11 of thebody 2 is produced in the form of a part which is thicker thanpreviously and at least three housings are made there to accommodate thethree respective solenoid valves, namely:

-   -   a housing 12 designed to accommodate the pre-blowing solenoid        valve and brought into communication with the annular passage 10        by a radial conduit 13;    -   a housing 14 designed to accommodate the blowing solenoid valve        and brought into communication with the annular passage 10 by a        radial conduit 15;    -   a housing 16 designed to accommodate the exhaust solenoid valve        and brought into communication with the annular passage 10 by a        radial conduit 17.

In the simplified drawing given in FIG. 1, only the housings of thesolenoid valves are shown, whilst the solenoid valves themselves are notshown (concrete examples thereof will be given below).

In the example of FIG. 1, the housings 12, 14 and 16 are schematized inthe form of rotating cylindrical housings with axes substantiallyparallel to the axis of the aforementioned bore 3. Nevertheless, otherarrangements are possible and examples will be given below.

So that at the end of blowing the blowing fluid is discharged veryrapidly and so that the mold might be opened as quickly as possible inview of increased functioning speed, it is desirable that the exhaustconduit be oversized, as shown for the radial conduit 17. After blowing,the fluid which is discharged is still at a significant pressure and maybe recuperated to be directed toward a source of fluid at moderatepressure (for example for the pre-blowing). In this case, a fourthhousing is provided in the body 2 to receive a solenoid valve forrecycling (which is actuated after blowing, whilst the exhaust solenoidvalve is actuated last for the elimination of the remainder of theblowing fluid).

It could be provided that each housing 12, 14, 16 is machined so as todefine, directly in the body 2, the chamber of the solenoid valveadapted to accommodate the mobile core forming the opening/closing valvemember. Such a solution certainly offers the advantage of optimalstructural simplification. This solution may have an additionaladvantage which will be examined below. Nevertheless, this solution alsoleads to restrictions for maintenance: in the event of problems with asolenoid valve, it is the whole of the relevant part of the body 2, eventhe body 2 in its entirety, which has to be dismantled, even replaced. Alonger time for maintenance and increased costs result.

To avoid these drawbacks, it may therefore prove more advantageous as awhole to resort to solenoid valve cartridges, available in the form of amodule adapted to be positioned in a respective housing or to be easilyand rapidly withdrawn therefrom. This solution is, therefore,particularly economical for maintenance.

It will be noted that the housings 12, 14, 16 are designed to receivethe respective solenoid valve itself (i.e. the chamber accommodating themobile core forming the valve member and the seat thereof), the cover ofthe solenoid valve bearing externally against the face of the mold,whilst the control device of the solenoid valve remains outside thehousing: a concrete example of the arrangement will be indicated below.

FIGS. 2A, 2B and 2C show a concrete embodiment implementing a variant ofthe arrangements of FIG. 1. In this concrete embodiment, the housings12, 14 (FIG. 2A) and 16 (FIG. 2B) are arranged radially around the bore3, such that the body 2 may be produced in a much more compact form inthe axial direction. Furthermore, the manufacture of the body issimplified and the access to the solenoid valves for maintenance iseasier.

FIGS. 2A, 2B and 2C clearly show the guide means, integral with the body2, of the elongating rod which comprise a tubular guide part 18interposed between the elongating rod 9 which is inside thereof and themobile nozzle 4 which is outside thereof.

The housing 12 which extends radially to the base of the body 2accommodates a solenoid valve cartridge 19. The solenoid valve cartridge19 comprises a housing 20 defining a chamber 21 accommodating a mobilecore 22 or piston. The housing 20 defines, in the chamber 21, a seat 23adapted to receive in sealing abutment the head of the mobile core 22forming the valve member. The wall of the housing 20 is perforated by atleast one aperture 24 communicating with a conduit 25 for supplyingpre-blowing fluid at moderate pressure, said conduit 25 passing throughthe body 2 substantially parallel to the bore 3.

A cover 26 for closing the housing 20 of the solenoid valve is fixed tothe wall of the body 2. The control device (not shown in these figures),generally of the pneumatic type, may be mounted on this cover 26.

The housing 20 of the solenoid valve cartridge 19 comprises, at its endturned radially inwards, a hole aligned with the respectiveaforementioned radial conduit 13, perforated in the base of the housing12 and opening out into the bore 3, these two aligned holes togetherconstituting a radial conduit denoted in its entirety by the referencenumeral 31.

The housing 14 which extends radially opposite the housing 12, beingdiametrically opposed thereto, accommodates an identical solenoid valvecartridge, with an identical arrangement to that disclosed above,connected to a conduit 27 for supplying blowing fluid at high pressure.

The housing 16 (FIG. 2B) which extends radially by being offset by 90°relative to the aforementioned housings 12 and 14, accommodates anidentical solenoid valve cartridge, with an identical arrangement tothat disclosed above, with the exception that the chamber 21 of thesolenoid valve cartridge is shown (by way of example) in connection witha silencer device 28; the communication apertures 24 may, in this case,have a larger section and/or be of greater number. The silencer device28 is shown in the form of a double-walled tubular element defining anelongated annular chamber. Said tubular element is fitted onto aprojecting cylindrical part of the body 2 defining the housing 16; itsexternal wall is perforated by a multiplicity of exhaust holes. Thesolenoid valve control device (not shown) may be mounted on the body 2inside the silencer device 28 or even mounted at the free end of thesilencer device.

The blowing device 1 is shown in FIGS. 2A and 2B in the non-functioningposition, the pre-blowing solenoid valves (housing 12) and blowingsolenoid valves (housing 14) being closed and the exhaust solenoid valve(housing 16) being open, the mobile nozzle 4 and the elongating rod 9being retracted. In FIG. 2C (which is a view similar to that of FIG. 2A)the blowing device 1 is shown in a first position, ready forpre-blowing, but the pre-blowing solenoid valve (housing 12) is not yetactuated. In this first position, only the mobile nozzle 4 has beenactuated and brought into position on the neck 6 of the blank 7 which itcaps in a sealed manner by bearing against the flange 8. In thisposition, radial apertures 29 distributed over the periphery of themobile nozzle 4, are exposed by the tubular guide part 18 of the guidemeans and establish a link between the volume defined by the blank 7 andthe lower end of the mobile nozzle 4, on the one hand, and, on the otherhand, an annular counterbore 30 which is made in the face of the bore 3and into which the conduits 31, for communicating with the threerespective solenoid valves, open.

In FIG. 3 a concrete variant of the blowing device 1 of FIGS. 2A-2C isshown in plan view. The design of the assembly remains substantiallysimilar to that disclosed above (the control devices 32 being shown inthis case in position on the covers 26 of the solenoid valves) with theexception, however, that a supplementary solenoid valve is provided forrecycling the residual pressurized fluid at the end of the blowing step,in place of the single exhaust solenoid valve shown in FIG. 2B. To thisend, the body 2 comprises two parallel housings 16 a, 16 b, respectivelyconnected by two respective conduits 17 a, 17 b, no longer directly tothe bore 3, but to the radial conduits 13 and 15, respectively,associated with the housings 12 and 14.

In a very schematic manner, a further variant of a blowing deviceimplementing the arrangements according to the invention is shown inFIG. 4. In this FIG. 4, only the body 2 is shown with the bore 3, inaddition to the three housings 12, 14, 16 which communicate with thebore 3 by respective radial conduits 13, 15 and 17 and which aredesigned to accommodate the pre-blowing, blowing and exhaust solenoidvalves respectively. This variant differs from that of FIG. 1 by thearrangement of housings 12, 14 and 16 which are not parallel to the bore3, but which are transverse to said bore and also differs from those ofFIGS. 2A-2C and 3 by the fact that the housings are not radial, butoffset laterally to the bore 3. This arrangement, as those of FIGS.2A-2C and 3, allows the height of the body 2 to be markedly reduced andmaintains the bore 3 in a central position in the body. If necessary, afourth housing may be provided for a recycling solenoid valve;nevertheless, this arrangement requires free access to be available tothe four sides of the body 2, which may not be possible in certainconfigurations of the device.

An advantage with this compact configuration lies in the fact that itmay be implemented not in the body supporting the mobile nozzle 4 butdirectly in the bell-shaped end of a bell nozzle (type of nozzle shownin FIG. 1 of the document FR 2 764 544): the body 2 shown in FIG. 4 isthus the body of the bell arranged according to the invention.

The arrangements according to the invention lead to a very markedreduction in the dead volume, and thus to a very significant reductionin the volume of pressurized fluid required for the pre-blowing/blowingof a container. For clarification, in a conventional blowing devicehaving a dead voluume in the order of 186 cm³, the implementation ofintegrated solenoid valves in the body of the blowing device may make itpossible to conceive reducing the dead volume to approximately 18 cm³,namely a remarkable saving of 168 cm³.

If the arrangement shown in FIG. 2A is considered with each solenoidvalve arranged radially relative to the central bore 3, it is possibleto reduce further the dead volume constituted by the conduit 31 formingthe communication through the lateral wall of the body defining the bore3 and the end wall of the housing 20 of the solenoid valve. In FIG. 5,only one part (the part located on the left) of FIG. 2A is reproduced,showing a single solenoid valve, with the difference that the mobilecore 22 is, in this case, mounted directly in the housing 14, machinedto this end, according to a configuration mentioned above. In this case,the chamfered conical edge of the front face 34 of the mobile core 22cooperates with an annular tapered seat 33 which is formed at the end,turned towards the inside, of the housing 14, by being machined directlyin the body 2. The conicity of the seat 33 may thus be such that thefront face 34 of the piston is flush with the lateral wall of the bore3. This front face 34 may preferably be curved inwards so as to bewithin the continuity of said lateral wall of the bore 3. The conduit 27may thus open out as near as possible to the seat 33, such that due tothis arrangement, the dead volume downstream of the mobile core 22,between the conduit 27 and the bore 3, may be very significantlyreduced.

1-12. (canceled)
 13. A device for blowing, by means of a pressurizedfluid, containers from thermoplastic blanks of which the body isenclosed in a blowing mold, said device comprising a nozzle comprisingan end formed to be functionally and sealingly connected to the neck ofa blank and comprising a plurality of solenoid valves for selectivelyconnecting said nozzle to, respectively, a source of fluid at moderatepressure for pre-blowing, a source of fluid at high pressure for blowingand an exhaust for discharging the pre-blowing/blowing fluid, wherein abody associated mechanically with the nozzle incorporates at least onehousing which is adapted to accommodate one of the solenoid valves andwhich is selectively in communication with the nozzle, wherein eachhousing extends parallel to the axis of the nozzle from the upper faceof the body, and wherein each housing is formed to receive a respectivesolenoid valve cartridge.
 14. The device as claimed in claim 13, whereinit is the body supporting the nozzle which is provided with saidhousing.
 15. The device as claimed in claim 13 in which the nozzle isterminated below by a bell-shaped end part, wherein it is the body ofthe bell terminating the nozzle which is designed with the housing. 16.The device as claimed in claim 13, wherein the device for controllingthe solenoid valve cartridge is mounted outside the housing.
 17. Thedevice as claimed in claim 16, further comprising an exhaust solenoidvalve associated with a device acting as a silencer.
 18. The device asclaimed in claim 13, wherein the device is equipped with at least twosolenoid valves associated respectively with a circuit for recyclingpressurized fluid at residual pressure, as a result of the blowing, andwith an exhaust and wherein the nozzle body is provided with fourhousings for these four respective solenoid valves.
 19. The deviceaccording to claim 13, wherein the housing is configured such that amajority of the solenoid valve is disposed inside of the body in whichthe housing is formed.
 20. The device according to claim 13, wherein thehousing comprises a recess formed in the body that extends from anexternal surface of the body to an axial bore in the body that housesthe nozzle.
 21. A device for blow-molding thermoplastic containers fromblanks disposed in a mold by means of pressurized fluid, theblow-molding device comprising: a nozzle comprising a distal endconfigured to form a seal with the blank or the mold; a body comprisingan axial bore, wherein the nozzle is slidably engaged in the axial bore;at least one solenoid valve for selectively connecting the nozzle to asource of fluid at moderate pressure for pre-blowing, a source of fluidat high pressure for blowing, or an exhaust for discharging thepre-blowing/blowing fluid; wherein a majority of the at least onesolenoid valve is disposed in a housing in the body; and wherein saidhousing is formed to receive a respective solenoid valve cartridge. 22.The device according to claim 21, wherein the housing comprises a recessformed in the body.
 23. The device according to claim 21, wherein thehousing extends from an external surface of the body to the axial bore.24. The device according to claim 21, wherein the housing extendsradially from the nozzle, such that a core of the solenoid valvetranslates in a radial direction relative to the nozzle.
 25. The deviceaccording to claim 21, wherein the housing is configured such that the afront face of the at least one solenoid valve is flush with the innerwall of the nozzle when the solenoid valve is in a closed position. 26.The device according to claim 13, wherein the housing is configured suchthat the entire solenoid valve is disposed inside of the body in whichthe housing is formed.
 27. The device according to claim 21, wherein thehousing is configured such that the entire solenoid valve is disposedinside of the body in which the housing is formed.
 28. A device forblowing, by means of a pressurized fluid, containers from thermoplasticblanks of which the body is enclosed in a blowing mold, said devicecomprising a nozzle comprising an end formed to be functionally andsealingly connected to the neck of a blank and comprising a plurality ofsolenoid valves for selectively connecting said nozzle to, respectively,a source of fluid at moderate pressure for pre-blowing, a source offluid at high pressure for blowing and an exhaust for discharging thepre-blowing/blowing fluid, wherein a body associated mechanically withthe nozzle incorporates at least one housing which is adapted toaccommodate a solenoid valve and which is selectively in communicationwith the nozzle; wherein each housing extends transversely to the nozzleby being offset laterally relative to a bore accommodating said nozzle;and wherein each housing is formed to receive solenoid valve cartridge.